1. Field of the Invention
The present invention relates to a highly versatile burner for a gas cooking range.
More particularly, the invention relates to a burner for a gas cooking range normally used in a domestic environment and having a broad operating range.
2. Description of the Prior Art
As is known, gas-fired burners of the single-, double- or triple-ring type are currently available and are designed to provide the greatest possible turn-down ratio while maintaining the maximum and minimum possible heat emissions and providing the highest possible combustion efficiency and pollutant reduction.
In general, gas-fired burners of the Venturi type (also known as atmospheric burners), i.e., burners that operate with primary air aspirated naturally from the environment that surrounds the burner, have a turn-down ratio between 6 and 7. In practice, and by way of example, this entails that standard gas burners with a maximum heat emission of 6000–7000 BTU/h have their minimum possible heat emission set to approximately 1000 BTU/h.
The end user, i.e., the user of the gas burner, perceives the turn-down ratio in terms of ease of use, flame adjustment, flexibility in use, and also as the minimum possible flame that does not cause a flame-out.
Substantially, the end user has the following requirements.
First of all, the heat emission of the burner should be as high as possible (for example 20,000–40,000 BTU/h). This is the most powerful maximum flame, which produces the shortest possible time for heating, boiling, etc.
It is in fact important to heat certain foods very rapidly, so that they do not lose their organoleptic properties; alternatively, this high heat emission requirement arises when, for example, one wishes to boil water in pots that have a thick steel bottom.
Secondly, the burner should have a minimum possible heat emission that is lower than for example approximately 600 BTU/h.
The minimum possible heat emission is used for example when using small pots or coffeepots, or in the case of delicate foods or ingredients, such as chocolate, butter, etc.
It is important to have a broad flame adjustment between the two upper and lower heat emission limits cited above.
Also, flame adjustment must be extremely accurate as regards the possibility to affect the size of the flame.
Also, it is important for the end user that the adjustment that is performed to pass from one flame size to another is such that return to the original flame size occurs with the flame adjustment knob set to the same position used previously (this phenomenon is termed “system hysteresis”).
The user must be able to adjust the flame by turning for example the knob to different positions and to return to the initial adjustment by returning the knob exactly to the position in which it was when adjustment began.
In view of the wide variety of sizes and materials used for pots, it would be ideal to have a heated surface area that is large enough to cover any available pot or vessel size.
The aim of the present invention is to provide a gas-fired burner for cooking ranges that is highly versatile and allows to provide the user with a means for reducing the input of heat into the vessel or container arranged on the cooking range, in order to reduce the overheating or burning of delicate foods and at the same time provide fine adjustment of the flame, so as to ensure the maximum possible heat emission from the gas burner.
An object of the present invention is to provide a gas-fired burner for cooking range that allows to have a broad operating range, from a very high heat emission to a very low heat emission, without flame-outs.
A further object of the present invention is to provide a gas-fired burner for cooking range that allows to have a flame adjustment between the upper heat emission limit and the lower heat emission limit that is extremely accurate and precise.
A further object of the present invention is to provide a gas-fired burner for cooking range that allows to have a large heat source surface area.
A further object of the present invention is to provide a gas-fired burner for cooking range that is highly reliable, relatively simple to provide, and at competitive costs.